[SCTP]: Rewrite of sctp buffer management code

This patch introduces autotuning to the sctp buffer management code
similar to the TCP.  The buffer space can be grown if the advertised
receive window still has room.  This might happen if small message
sizes are used, which is common in telecom environmens.
New tunables are introduced that provide limits to buffer growth
and memory pressure is entered if to much buffer spaces is used.

Signed-off-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: Vlad Yasevich <vladislav.yasevich@hp.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 5 insertions, 0 deletions

diff --git a/include/net/sctp/sctp.h b/include/net/sctp/sctp.h
index c9cc00c85782..d5a1ddc7483f 100644
--- a/include/net/sctp/sctp.h
+++ b/include/net/sctp/sctp.h
@@ -469,6 +469,11 @@ static inline void sctp_skb_set_owner_r(struct sk_buff *skb, struct sock *sk)
         skb->sk = sk;
         skb->destructor = sctp_sock_rfree;
         atomic_add(event->rmem_len, &sk->sk_rmem_alloc);
+        /*
+         * This mimics the behavior of
+         * sk_stream_set_owner_r
+         */
+        sk->sk_forward_alloc -= event->rmem_len;
 }
 
 /* Tests if the list has one and only one entry. */